As it is right now the public has to pay twice for publicly funded research. First through tax dollars that go towards the federal grants paying for the research, and second through access fees to journals. The problem is not whether such research results should be open-access, which I think most people would agree to, it is how exactly to go about that. With the current incentive scheme for academic professionals, they need to consistently publish and publish in high impact factor journals to guarantee continued advancement in their field. Right now the only open source alternatives are nowhere near the prestige of the existing journal behemoths and it would be a competitive disadvantage for a researcher to publish in a lower ranked journal when they could publish in a higher ranked journal.
How to get around this problem? You could make it a grant requirement for any researcher in Canada who receives federal grant funding to publish in an open access journal and this at least starts to level the playing field within a national context but this may still hurt a researcher's reputation internationally which can be important for developing collaborations in the field. An alternative is to set up a system where we create something of a centralized online library that pays for anytime access to any federally funded articles to the journals that hold them and then provide those at request to any member of the Canadian public. This would require again though more investment of funds but I think it would be small relative to the amount of money spent on the grants themselves. This would not impact that researchers in any way that I can think of.